Each summer, Greenland’s ice sheet — the world’s second-largest expanse of ice, measuring three times the size of Texas — begins to melt. Pockets of melting ice form hundreds of large, “supraglacial” lakes on the surface of the ice. Many of these lakes drain through cracks and crevasses in the ice sheet, creating a liquid layer over which massive chunks of ice can slide. This natural conveyor belt can speed ice toward the coast, where it eventually falls off into the sea. In recent years, scientists have observed more lakes forming toward the center of the ice sheet — a region that had been previously too cold to melt enough ice for lakes to form.

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When people think of genetically modified organisms, food crops like GM corn and soybeans usually come to mind. But engineering more complex living things is now possible, and the controversy surrounding genetic modification has now spread to the lowly mosquito, which is being genetically engineered to control mosquito-borne illnesses.

A U.K.-based company, Oxitec, has altered two genes in the Aedes aegypti mosquito so that when modified males breed with wild females, the offspring inherit a lethal gene and die in the larval stage. The state agency that controls mosquitos in the Florida Keys is awaiting approval from the federal government of a trial release of Oxitec’s genetically modified mosquitos to prevent a recurrence of a dengue fever outbreak. But some people in the Keys and elsewhere are up in arms, with more than 155,000 signing a petition opposing the trial of genetically engineered mosquitoes in a small area of 400 households next to Key West. 

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More than 200,000 people flooded the U.S. Forest Service with comments over the last month calling for the agency to reject a plan for roads and infrastructure that would enable construction of a mega-development on the Grand Canyon’s doorstep. 

The proposed roads, sewers and other utilities would pave the way for a multinational developer to transform the 580-resident community of Tusayan, Ariz., from a small, quiet tourist town into a sprawling complex of high-end homes, retail stores and restaurants only a mile from the Grand Canyon National Park boundary. The development threatens groundwater that feeds the Grand Canyon’s creeks, springs and seeps, endangering some of the park’s most important and biodiverse wildlife habitat. 

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Investigadores del Laboratorio de Física de Plasma de Princeton, del Departamento de Energía de Estados Unidos (PPPL) por primera vez han simulado la formación de estructuras llamadas "plasmoides" durante la Inyección Coaxial de “Helicidad” (CHI), un proceso que podría simplificar el diseño de plantas de energía a base de fusión, conocidos como “tokamaks”. Los resultados, publicados en la revista Physical Review Letters, implican la formación de plasmoides en el gas de plasma, caliente y cargado, que es el combustible de las reacciones de fusión. Estas estructuras (redondas) transportan corriente que podría eliminar la necesidad de solenoides, grandes bobinas magnéticas que serpentean por el centro de los tokamaks de hoy, para iniciar el plasma y completar el campo magnético que confina el gas caliente.

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As air pollution spikes in Europe’s cities prompt car-free days and talk of banning diesel cars, it’s easy to forget the other culprits behind the air quality crisis: diesel machines. Known in legislation by the innocuous term ‘non-road mobile machinery’, their air pollutant emission limits are now finally under revision.

The last directive dated back to 1997 and the new rules will set standards for decades to come. Air pollution is causing more than 450,000 premature deaths every year in Europe and a recent Eurobarometer survey confirmed that air pollution is now the biggest environmental concern of European citizens. Efficient regulation of emissions sources is therefore key to mitigating the exposure of citizens to air pollution.

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At times during the past 10,000 years, cottontails and hares reproduced like rabbits and their numbers surged when the El Niño weather pattern drenched the Pacific Coast with rain, according to a University of Utah analysis of 3,463 bunny bones. The study of ancient rabbit populations at a Baja California site may help scientists better understand how mammals that range from the coast to the interior will respond to climate change, says anthropology doctoral student Isaac Hart. He is first author of the study to be published in the July issue of the journal Quaternary Research.

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